CNN) -- A grand jury in Texas declined to indict the driver of a parade float involved in a deadly accident with a train during a November 15 parade, a prosecutor said Wednesday.

Four people were killed when the flatbed truck driven by Dale Andrew Hayden was struck by a train during a parade to honor the military.

Midland County prosecutor Eric Kalenak said the 12 members of the grand jury decided against indicting Hayden, who last month was cleared by Midland police.

Hayden was driving the last flatbed truck in the parade and was crossing the tracks when an eastbound Union Pacific train slammed into the float, killing Marine Corps Chief Warrant Officer 3 Gary Stouffer, 37; Army Sgt. Maj. Lawrence Boivin, 47; Army Sgt. Joshua Michael, 34; and Army Sgt. Maj. William Lubbers, 43.

At least 12 other people were injured.

The National Transportation Safety Board said in December that the grade-crossing warning system, which consists of a bell, lights and a gate, operated as designed, giving a 20-second warning of the train's arrival. The truck entered the crossing and the gate lowered, tipping over flag stands on the float.

The board re-created the accident as part of an investigation.

Kevin Glasheen, an attorney who represents the family of one of the soldiers killed and two people who were injured, said his clients feel Hayden is a victim.

"We believe the event was due to the short warning which we believe is cause of the accident," Glasheen said Wednesday.